Valeant Pharmaceuticals International, Inc. says it had a US$373.7 million loss in its first quarter and its adjusted income was down 37 per cent from a year earlier.

The Quebec-based drug maker's loss, reported in U.S. currency, was equal to $1.08 per share.

That compared with a year-earlier profit of $97.7 million or 29 cents per share -- prior to a series of setbacks that began taking a toll on Valeant last summer.

Valeant's adjusted earnings were $442.6 million or $1.27 per share, which was down from $704.2 million or $2.05 per share in the first quarter of 2015.

Revenue was up nine per cent to $2.37 billion -- largely from acquisitions and their growth since purchased by Valeant.

Valeant also issued revised estimates for the full 2016 financial year. It now expects revenue of between $9.9 billion and $10.1 billion and adjusted earnings of between $6.60 and $7 per share.